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See detailOn the origins of historical linguistics. Materials and proposals for the Italian case
Droixhe, Daniel ULg

in Gambarara, D.; Formigari, L. (Eds.) Historical roots of linguistics theories (1995)

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See detailOn the parameters of absorbing layers for shallow water models
Modave, Axel ULg; Deleersnijder, Eric; Delhez, Eric ULg

in Ocean Dynamics (2010), 60(1), 65-79

Absorbing/sponge layers used as boundary conditions for ocean/marine models are examined in the context of the shallow water equations with the aim to minimize the reflection of outgoing waves at the ... [more ▼]

Absorbing/sponge layers used as boundary conditions for ocean/marine models are examined in the context of the shallow water equations with the aim to minimize the reflection of outgoing waves at the boundary of the computationaldomain. The ptimization of the absorption coefficient is not an issue in continuous models, for the reflection coefficient of outgoing waves can then be made as small as we please by increasing the absorption coefficient. The optimization of the parameters of absorbing layers is therefore a purely discrete problem. A balance must be found between the efficient damping of outgoing waves and the limited spatial resolution with which the resulting spatial gradients must be described. Using a one-dimensional model as a test case, the performances of various spatial distributions of the absorption coefficient are compared. Two shifted hyperbolic distributions of the absorption coefficient are derived from theoretical considerations for a pure propagative and a pure advective problems. These distribution show good performances. Their free parameter has a well-defined interpretation and can therefore be determined on a physical basis. The properties of the two shifted hyperbolas are illustrated using the classical two-dimensional problems of the collapse of a Gaussianshaped mound of water and of its advection by a mean current. The good behavior of the resulting boundary scheme remains when a full non-linear dynamics is taken into account. [less ▲]

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See detailOn the Parameters of the Perfectly Matched Layer in Discrete Contexts
Modave, Axel ULg; Delhez, Eric ULg; Geuzaine, Christophe ULg

in Proceedings of the 10th International Conference on Mathematical and Numerical Aspects of Waves (WAVES 2011) (2011, July 26)

Perfectly Matched Layer (PML) techniques are widely used for dealing with unbounded problems. However their performance depends critically on both an absorption coefficient and the numerical method. The ... [more ▼]

Perfectly Matched Layer (PML) techniques are widely used for dealing with unbounded problems. However their performance depends critically on both an absorption coefficient and the numerical method. The coefficient is generally tuned by using costly and case-dependent optimization procedures or set empirically. In this paper we present some efficient profiles of the coefficient that allow to avoid any tuning in discrete contexts. These profiles are compared by means of two benchmarks with different numerical methods. [less ▲]

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See detailOn the Performance of the LISP Beta Network
Coras, Florin; Saucez, Damien; Iannone, Luigi et al

in IFIP Networking (2014, June)

The future Internet has been a hot topic during the past decade and many approaches towards this future Internet, ranging from incremental evolution to complete clean slate ones, have been proposed. One ... [more ▼]

The future Internet has been a hot topic during the past decade and many approaches towards this future Internet, ranging from incremental evolution to complete clean slate ones, have been proposed. One of the proposition, LISP, advocates for the separation of the identifier and the locator roles of IP addresses to reduce BGP churn and BGP table size. Up to now, however, most studies concerning LISP have been theoretical and, in fact, little is known about the actual LISP deployment performance. In this paper, we fill this gap through measurement campaigns carried out on the LISP Beta Network. More precisely, we evaluate the performance of the two key components of the infrastructure: the control plane (i.e., the mapping system) and the interworking mechanism (i.e., communication between LISP and non-LISP sites). Our measurements highlight that performance offered by the LISP interworking infrastructure is strongly dependent on BGP routing policies. If we exclude misconfigured nodes, the mapping system typically provides reliable performance and relatively low median mapping resolution delays. Although the bias is not very important, control plane performance favors USA sites as a result of its larger LISP user base but also because European infrastructure appears to be less reliable. [less ▲]

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See detailOn the Period of the W UMa System epsilon CrA
Manfroid, Jean ULg; Lunel, M.; Bergeat, J. et al

in Information Bulletin on Variable Stars (1984), 2479

Not Available

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See detailOn the Periodicity of Morphic Words
Halava, Vesa; Harju, Tero; Kärki, Tomi et al

in Lecture Notes in Computer Science (2010), 6224

Given a morphism h prolongable on a and an integer p, we present an algorithm that calculates which letters occur infinitely often in congruent positions modulo p in the infinite word hω(a). As a ... [more ▼]

Given a morphism h prolongable on a and an integer p, we present an algorithm that calculates which letters occur infinitely often in congruent positions modulo p in the infinite word hω(a). As a corollary, we show that it is decidable whether a morphic word is ultimately p-periodic. Moreover, using our algorithm we can find the smallest similarity relation such that the morphic word is ultimately relationally p-periodic. The problem of deciding whether an automatic sequence is ultimately weakly R-periodic is also shown to be decidable. [less ▲]

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See detailOn the periodontal ligament representation in orthodontic tooth movement modelisation
Mengoni, Marlène ULg; Ponthot, Jean-Philippe ULg

Conference (2011)

Orthodontic tooth movement (OTM) is the result of bone remodeling at the interface with the periodontal ligament (PDL) around a mechanically loaded tooth in response to a biomechanical stimulus. Modeling ... [more ▼]

Orthodontic tooth movement (OTM) is the result of bone remodeling at the interface with the periodontal ligament (PDL) around a mechanically loaded tooth in response to a biomechanical stimulus. Modeling of the PDL therefore plays an important role in the process of modeling OTM. However when producing a finite element model from clinical computer tomography data, the PDL cannot be segmented and its geometry is approximated by many authors from the root geometry. The aim of this study is to propose alternatives to a geometrical representation of the PDL using either simple spring elements between the teeth and alveolar bone or bilateral sticking contact conditions. Results consist in a comparison of the hydrostatic and Von-Mises stresses in the bone along the root as well as the strain energy used in a bone remodeling algorithm when a 1N force is applied to a single rooted tooth crown. While both models can well represent the pressure (hydrostatic stress) transfer from the tooth to the bone, the bilateral sticking contact conditions show better results to transfer the shear stress as well as the strain energy. [less ▲]

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See detailOn the periphery of Nollywood: Nigerian video filmmaking in Italy and the emergence of intercultural aesthetics
Jedlowski, Alessandro ULg

in Lombardi-Diop, Cristina (Ed.) Postcolonial Italy: Challenging National Homogeneity (2012)

Nigerian video films are widely consumed among Africans leaving in Italy, but their impact on the Italian society is not limited to their consumption. Two Nigerian video production companies, directly ... [more ▼]

Nigerian video films are widely consumed among Africans leaving in Italy, but their impact on the Italian society is not limited to their consumption. Two Nigerian video production companies, directly connected to the Nigerian system of production and distribution, have emerged in Northern Italy over the past few years, the IGB Film and Music Industry based in Brescia and the GVK (Giving Vividly with Kindness) based in Turin. These production companies shoot their films in Italy to sell them mainly within the Nigerian diaspora in Italy and on the Nigerian video market, metaphorically locating Italy on the periphery of the Nigerian production system. This article discusses the results of a research about these production companies through two main sections that focus on two different aspects of the phenomenon. The first section presents an analysis of the films produced by these companies, connecting it to the production strategies that they developed in order to be able to find a place within the Italian economic system. The two companies took very different marketing choices. On one hand, the IGB has oriented its production mainly toward a Nigerian audience, maintaining very specific aesthetic and narrative attributes, directly connected to Nollywood's cinematic style. On the other hand the GVK, after its first release in 2005, decided to change strategy, starting a partnership with an Italian director and trying to produce an intercultural product that could ideally work for both Nigerian and Italian audiences. Comparing these two strategies of production and the aesthetic choices that originated from them this article explores the process of construction of intercultural aesthetics in these videos. The second section presents an analysis of the contents of the video films produced by these companies, and analyzes the particular perspective on the experience of migration that they propose. These video films locate themselves at the point of convergence between the emergence of a migrant cinema in Italy and a specific phase of development of the Nigerian video film industry, characterized by a significant focus on the diaspora in terms both of production and marketing. As a consequence of it, the Nigerian videos produced in Italy, as other films recently produced in Italy by migrant directors, are able to represent the experience of migration from an internal perspective, but they do it by adopting the commercial film genres that characterize Nollywood films, in opposition to the more artistic and intellectually oriented style of other migrant films. The conjuncture of these two trends determines a very original representation of migration, which this article analyzes and interprets. [less ▲]

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See detailOn the perspectives of using XMM to study fundamental parameters of early-type stars
Rauw, Grégor ULg; van der Hucht, K. A.; Mewe, R. et al

in Wolf-Rayet Phenomena in Massive Stars and Starburst Galaxies (1999)

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See detailOn the Photometric Variations of HD 28843 and HD 29009
Manfroid, Jean ULg; Mathys, G.

in Information Bulletin on Variable Stars (1984), 2551

Not Available

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See detailOn the Piano Key Weir hydraulics
Machiels, Olivier ULg; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in Rutschmann, Peter; Grünzner, Markus; Stephan, Hötzl (Eds.) Proceedings of 2nd IAHR Europe Congress (2012)

The Piano Key Weir (PKW) is a kind of labyrinth weir with a geometry that uses overhangs to reduce the base length. The PKW can thus be directly placed on the crest of an existing dam. Together with its ... [more ▼]

The Piano Key Weir (PKW) is a kind of labyrinth weir with a geometry that uses overhangs to reduce the base length. The PKW can thus be directly placed on the crest of an existing dam. Together with its high discharge capacity for low heads (up to four times as high as an ogee-crested weir of same length), this geometric feature makes the PKW an interesting solution for dam rehabilitation and for new dam projects with a high level of constraints (design discharge, available space, reservoir storage, ...). PKW has been initially designed in 2001 and built for the first time in 2006 by “Electricité de France (EDF)”. Even if the first experimental studies confirmed its appealing discharge capacities, the flow upstream, over and downstream of this complex structure is still poorly described. Following a 3 years intensive experimental and numerical study of PKW hydraulics, the paper presents a general description of the hydraulic behavior of the PKW. It aims to explain the influence of the large set of geometric parameters on the discharge capacity. The assumptions of the study link various phenomenons depicted in the literature about PKW and an evaluation of their relative influence on the PKW efficiency is given. The role of the crests shape, the crests submersion, the nappes interactions, the crests approach conditions, the position of the control section and the head losses are analyzed. Design advices are also given. [less ▲]

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See detailOn the policy implications of changing longevity
Pestieau, Pierre ULg; Ponthiere, Grégory ULg

in CESifo Ecoonmic Studies (2014), 60

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See detailOn the possibility of self-enrichement in globular clusters
Parmentier, Geneviève ULg; Jehin, Emmanuel ULg; Magain, Pierre ULg et al

in Noels-Grötsch, Arlette; Magain, Pierre; Caro, Denise (Eds.) et al Liege International Astrophysical Colloquia (2000)

Not Available

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See detailOn the Potential Effect of Increased Dietary Intake of Fruits and Vegetables on Biomarkers of Lipid Peroxidation in Type 2 Diabetes Patients
PINCEMAIL, Joël ULg; PAQUOT, Nicolas ULg; Cillard, J et al

in Journal of Pharmacy & Nutrition Sciences (2013), 3(3),

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See detailOn the potential increase of the oxidative stress status in patients with abdominal aortic aneurysm.
PINCEMAIL, Joël ULg; Defraigne, Jean-Olivier ULg; Cheramy-Bien, J. P. et al

in Redox Report : Communications in Free Radical Research (2012), 17(4), 139-44

BACKGROUND: Abdominal aortic aneurysm (AAA) is a major cause of preventable deaths in older patients. Oxidative stress has been suggested to play a key role in the pathogenesis of AAA. However, only few ... [more ▼]

BACKGROUND: Abdominal aortic aneurysm (AAA) is a major cause of preventable deaths in older patients. Oxidative stress has been suggested to play a key role in the pathogenesis of AAA. However, only few studies have been conducted to evaluate the blood oxidative stress status of AAA patients. METHODS AND RESULTS: Twenty seven AAA patients (mean age of 70 years) divided into two groups according to AAA size (</= 50 or > 50 mm) were compared with an age-matched group of 18 healthy subjects. Antioxidants (vitamins C and E, beta-carotene, glutathione, thiols, and ubiquinone), trace elements (selenium, copper, zinc, and copper/zinc ratio) and markers of oxidative damage to lipids (lipid peroxides, antibodies against oxidized patients, and isoprostanes) were measured in each subject. The comparison of the three groups by ordinal logistic regression showed a significant decrease of the plasma levels of vitamin C (P = 0.011), alpha-tocopherol (P = 0.016) but not when corrected for cholesterol values, beta-carotene (P = 0.0096), ubiquinone (P = 0.014), zinc (P = 0.0035), and of selenium (P = 0.0038), as AAA size increased. By contrast, specific markers of lipid peroxidation such as the Cu/Zn ratio (P = 0.046) and to a lesser extent isoprostanes (P = 0.052) increased. CONCLUSION: The present study emphasizes the potential role of the oxidative stress in AAA disease and suggests that an antioxidant therapy could be of interest to delay AAA progression. [less ▲]

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See detailOn the potential of extrasolar planet transit surveys
Gillon, Michaël ULg; Courbin, F.; Magain, Pierre ULg et al

in Astronomy and Astrophysics (2005), 442

We analyse the respective benefits and drawbacks of ground-based and space-based transit surveys for extrasolar planets. Based on simple but realistic assumptions about the fraction of lower main sequence ... [more ▼]

We analyse the respective benefits and drawbacks of ground-based and space-based transit surveys for extrasolar planets. Based on simple but realistic assumptions about the fraction of lower main sequence stars harboring telluric and giant planets within the outer limit of the habitable zone, we predict the harvests of fictitious surveys with three existing wide field optical and near-IR cameras: the CFHT-Megacam, SUBARU-Suprime and VISTA-IR. An additional promising instrument is considered, VISTA-Vis, currently under development. The results are compared with the harvests predicted under exactly the same assumptions, for the space missions COROT and KEPLER. We show that ground-based wide field surveys may discover more giant planets than space missions. However, space surveys seem to constitute the best strategy to search for telluric planets. In this respect, the KEPLER mission appears 50 times more efficient than any of the ground-based surveys considered here. KEPLER might even discover telluric planets in the habitable zone of their host star. [less ▲]

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See detailOn the Potential of Recommendation Technologies for Efficient Content Delivery Networks
Kaafar, Mohamed Ali; Berkovsky, Shlomo; Donnet, Benoît ULg

in Computer Communication Review (2013), 43(3), 74-77

During the last decade, we have witnessed a substantial change in content delivery networks (CDNs) and user access paradigms. If previously, users consumed content from a central server through their ... [more ▼]

During the last decade, we have witnessed a substantial change in content delivery networks (CDNs) and user access paradigms. If previously, users consumed content from a central server through their personal computers, nowadays they can reach a wide variety of repositories from virtually everywhere using mobile devices. This results in a considerable time-, location-, and event-based volatility of content popularity. In such a context, it is imperative for CDNs to put in place adaptive content management strategies, thus, improving the quality of services provided to users and decreasing the costs. In this paper, we introduce predictive content distribution strategies inspired by methods developed in the Recommender Systems area. Specifically, we outline different content placement strategies based on the observed user consumption patterns, and advocate their applicability in the state of the art CDNs. [less ▲]

Detailed reference viewed: 73 (3 ULg)